Hereinafter, the invention is described with respect to its application to processing of dairy products. It is contemplated that both the apparatus and the methods of the invention have application to a wide variety of industrial processes which require transferring of fluid components without introducing contaminating material into the processing enclosure. Thus, the disclosure of dairy processing herein is only illustrative, and is not limiting; whereby a variety of other processing industries are contemplated.
In the processing of dairy products, it is sometimes advantageous to add fluid to the closed aseptic processing system without introducing microbiological or other contamination into the processing system, or similarly to remove fluid from the closed aseptic processing system.
Some processors of dairy products have addressed this problem by attempting to keep sterile the rooms in which the processing takes place. Under the assumption that sterility is achieved, fluid is transferred into or out of the processing system through an open port in e.g. a tank. Keeping the room sterile is difficult; and the sterile room practice is, of course, expensive.
Other processors have addressed this problem of attempting aseptic transfer by attempting to control the amount of microbiological organisms immediately around the open port, as by using a fire ring around the open port. With the fire ring, it is contemplated that microbiological organisms in the vicinity of the open port are destroyed by the heat of the fire.
Still another known method of addressing aseptic transfer is to use a steam ring in place of the fire ring.
Another problem in the dairy processing industry is that the valves and pumps typically used to transfer, for example processed material from one tank to another are difficult to keep clean and sanitized. So special techniques, such as steam tracing, steam jacketing and the like of pumps and valves, have been developed to assure maintenance of aseptic conditions.
These steam-related procedures are time consuming and expensive, requiring a high level of training and skill on the part of the operators. Such complex procedures carry the usual risk of human error. Further, the high temperature inherent in steam creates a risk of the operators being burned. Finally, the heat brought into the plant by the steam must be removed by air conditioning. This adds to the overall cost of air conditioning the plant to maintain specified ambient plant conditions.
In my prior applications and patents mentioned above, from which this application depends, I disclose an aseptic fluid transfer system comprehending an aseptic plug, mounted into the tank wall. The plug is held temporarily mounted to and extending through the tank wall, by a metal tank adapter which is permanently welded into the tank wall, as taught in, for example my U.S. Pat. No. 4,941,517. An hypodermic or like needle can penetrate the plug, whereby the end of the needle protrudes into the interior of the tank. This establishes an aseptic penetration into the tank, whereupon fluid can be passed into or out of the tank, through the needle.
To transfer a larger quantity of fluid, a plurality of needles can be arranged in a needle bundle, with the needles arrayed in a pattern corresponding to the pattern of needle channels which extend through the plug. All the needles, as part of the needle bundle, should be pushed into the plug in the same operation whereby the ends of all the needles are ultimately disposed in the tank. Fluid is typically passed through all the needles in the needle bundle. The number of needles in the needle bundle thus determines in part the fluid flow capacity of the needle bundle.
In using a single needle to penetrate the plug, the operator selects an unused channel in the plug, aligns the needle with the channel, and pushes the end of the needle through the plug and into the tank.
When using a plurality of needles simultaneously as in e.g. a needle bundle, alignment of the needles, and pushing the plurality of ends of the needles through the plug is more difficult. Alignment is more complicated because all of the needles must be simultaneously aligned with respective channels. Pushing the needle ends through the plug is more difficult because the force required is proportional to the number of needles used, such that a person may not, without mechanical assistance, be able to push hard enough to make the needle ends penetrate into the tank.
It is an object of this invention to provide a fluid transfer station at a tank, the fluid transfer station including a needle bundle driver assembly, a mounting base on the tank, and a plug, the fluid transfer station being adapted to provide indexing of the needle bundle and the plug, and mechanical power to thereby drive a plurality of needle ends through the plug.
It is another object to provide a needle bundle adapted to be driven as part of the needle bundle driver assembly.
It is yet another object to provide a needle bundle holder to hold the needle bundle while the ends of the needles are driven through the plug and into the tank.
It is still another object to provide methods of simultaneously driving a plurality of needle ends through the plug and into the tank.
Another object of the invention is to provide methods of aseptically adding fluid to a processing system, or removing fluid therefrom, using a plurality of needles as the conduits of fluid transfer. Finally, it is an object to provide methods of aseptically transferring fluids into, or out of, a plurality of tanks using a single needle bundle driver assembly.